An end of a composite cylinder (40) is formed about an end connection assembly having two longitudinally arranged pieces (42a, 42b) having a contour which prevents the withdrawal of the end connection assembly from the cylinder. The two pieces of the end connection assembly are relatively forced apart and a snap ring (46) having a certain rest diameter is reduced in diameter and inserted into the end connection assembly to a position between the pieces. The snap ring then assumes its rest diameter positioned between the pieces, forcing them to maintain intimate contact with the inner surface of the cylinder, thus removing any residual gap from the assembly process and/or preloading the interface between the end of the composite cylinder and the end assembly prior to application of an axial load.